Typographical line-casting machine



April 13 1926. 1,580,296

B. J. J. GOULDING TYPOGRAPHICAL LINE CASTING MACHINE Filed April 21,. 1922 Patented Apr. 13, 1926.

if UNITED STATES PATENT onion; 1

BENJAMIN Josnrn JOHN eounnme, OF AL'lRINCI-IAM, cirnsrnnj'nnennivn, -As- SIGNOR T0 LINOTYPE AND MACHINERY LIMITED, or LONDON, ENGLAND, A BRIT- ISH COMPANY.

TYPOGRAPHICAL LINE-CASTING MACHINE.

Application filcd April 1, 1922. Serial no. 555,833.

To all whom it may ooncern: I

-Be it known that I, BENJAMIN osnrrr JOHN GOULDING, a subject of the King of Ireland, and residing at-Linotype and Machinery Works, Altrincham, n, the county of Chester, England, haveiinvented new and useful Improvements in Typographical Line-Casting Machines, of which the 01 lowing is a specification. r

This invention relates to typographlcal line-casting machines such as those known commercially under the trade mark Linotype and kindred machines, and it has for its object to ensure the manufacture of slugs which shall be better sulted for the production of stereotypes by the so-called dry flong method, than have been those heretofore produced by similar means.

The production of the just-mentioned dry flongs, as now practised'in many newspaper otfices, subjects the slugs to very heavy pressures, and if the slugs be'defective or spongy in the immediate vicinity of their prlnting edges as by the existence at those parts of blowholes, these pressures have a tendency to depress the said parts below heiglit-to-paper and may result in the production of corresponding depressions 1n the stereotypes cast from the flongs, and corresponding white or weak patches in the prints obtained from such stereotypes.

As is already Well known, the before-men tioned slugs are cast in a mold, to the front of which is presented a line of matrices as sembled in order of composition, the molten,

type metal being forced into the 'rear'of the mold through a throat leading from a pump which intermittently supplies the metal at the desired pressure.

The throat is moved into and out of contact with the mold, and during the nondelivering operations of the pump, the upper part of such throat is occupied by air which mostly escapes through shallow grooves usually formed for the purpose in the front face of the metal-pot mouthpiece, during the metal delivering operation of said pump.

It occasionally, however, does happen that some of this air becomes trapped in the moldwhen the metal is injected there- 'i into, with the result that .character-bearing edge,

formed in the slugs.

The invention will now be describedby reference to the accompanying drawing which is a vertical section of as muchvof" a' machineof the type before pa'rticularized as is necessaryto g'vea clear understanding of such invention. h Y v According to this-inventionthe beforementioned improved result is obtained by providing a small "air chamber 1, on, or as represented, preferably cast in, the upper part of the metal delivery throat 2, which latter, in other respects,-is of the ordinary well-known construction connecting at its lower end with the pump cylinder 3 and being provided at its upper end with the usual perforated mouth-piece 4. The

Y usual heating devices (not shown) guard blow 7 holes are against solidification of the metal in the pot throat and mouth-piece. v

The mouth-piece 4:, as ordinarily, is moved into and out of metal-tight contact with the back of the mold 5, carried by the mold wheel 6, and this mold, in turn, makes close contact with the back of the assembled line of matrices 7 Whleh is then held in casting position in the so-called first elevator 8.

I In the employment of a metal-delivery throat of the construction illustrated, it is found that some of the air in vsaid throat becomes trapped and compressed in the cham'berl during the metal-ejecting action ing action of said pump and the cooling and consequent shrinking of the slug in the mold, that air in expanding, exercises a more or less uniform pressure on the rapidly solidifying slug. By these means it is found that the resultant slugs are of more uniform texture throughout their substance, than are those as ordinarily constructed, and that, if

blow holes do occur in them, theseholes. are

generally located sutficiently far from the as to present nc of thepump, so that during the non-ejectdanger of that edge collapsing under-the pressures to which the slugs will ordinarily be exposed.

It has been found that the best results are obtained when the air chamber 1, is, as shown m the drawing, of approximately ovoid shape in transverse section, with the smaller end nearer to or directed towards the mouth-piece 4:, it being assumed that this particular form provides a freer access for the air into and out of the said chamber.

Having described my invention, I declare that what I claim and desire to secure by Letters Patent is 1. In a typographical line-casting machine, the combination of an air-vented mold, a pump for injecting molten metal into the mold, and a metal-delivery throat having a passage leading from the pump to the mold, the said throat being formed with an air chamber in open communication only with the passage through the throat, whereby the air compressed within said chamber during the pumping operation will exert pressure upon the rapidly solidifying metal within the mold when the pump pressure is relieved.

2. In a typographical line-casting ma chine, the combination of an air-vented mold, a pump for injecting molten metal into the mold, and a metal-delivery throat having a passage leading from the pump to the mold and provided with a mouth-piece at its delivery end, the said throat being formed adjacent the mouth-piece with an air chamber in open communication only With the passage through the throat, whereby the air compressed within said chamber during the pumping operation will exert pressure upon the rapidly solidifying metal within the mold when the pump pressure is relieved.

In a typographical line-casting machine, the combination with a metal-deliv ery throat of an air chamber in open connection only with the passage through said throat, the said air chamber being of approximately ovoid shape in transverse section with the smaller end directed towards the delivery or outlet end of the throat.

In' testimony whereof I have aflixed my signature hereto.

BENJAMlN JOSEPH JOHN GOULDING. 

